package com.example.test.a20240530;

import java.util.Scanner;

public class HJ26字符串排序 {
    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);

        String s = in.nextLine();

        char[] chars = s.toCharArray();

        selectSort(chars);
        for (int i = 0; i < s.length(); i++) {
            System.out.print(chars[i]);
        }

        //System.out.println((char) ('A' + 32));

    }

    public static void bubbleSort(char[] arr) {

        for (int i = 0; i < arr.length - 1; i++) {
            for (int j = 0; j < arr.length - i - 1; j++) {
                char c1 = arr[j];
                char c2 = arr[j + 1];
                if (!isLetter(c1) || !isLetter(c2)) {

                } else if (toLower(c1) > toLower(c2)) {
                    arr[j] = c2;
                    arr[j + 1] = c1;
                }
            }
        }
    }

    public static void selectSort(char[] arr) {
        for (int i = 0; i < arr.length; i++) {
            int index = i;
            char min = arr[index];

            if (!isLetter(min)) {
                continue;
            }

            for (int j = i + 1; j < arr.length; j++) {
                char c1 = arr[j];
                if (isLetter(c1)) {
                    if (toLower(min) > toLower(arr[j])) {
                        index = j;
                        min = arr[j];
                    }
                }
            }

            if (i != index) {
                arr[index] = arr[i];
                arr[i] = min;
            }
        }
    }

    public static boolean isLetter(char c) {
        if (c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z') {
            return true;
        } else return false;
    }

    public static char toLower(char c) {
        if (c >= 'A' && c <= 'Z') {
            c = (char) (c + 32);
        }
        return c;
    }
}
